RESEARCH ARTICLE
Impact of non-framework cation mixing on the structure and crystallization behavior of model high-level waste glasses
Nikhila Balasubramanya,
Zhenxuan Sun,
Mostafa Ahmadzadeh,
Saeed Kamali,
Daniel R. Neuville,
John S. McCloy,
Ashutosh Goel,
Nikhila Balasubramanya
Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854 USA
Search for more papers by this authorZhenxuan Sun
Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854 USA
Search for more papers by this authorMostafa Ahmadzadeh
School of Mechanical and Materials Engineering and Materials Science and Engineering Program, Washington State University, Pullman, Washington, USA
Search for more papers by this authorSaeed Kamali
Mechanical, Aerospace and Biomedical Engineering Department, University of Tennessee Space Institute, Tullahoma, Tennessee, USA
Department of Physics and Astronomy, Middle Tennessee State University, Murfreesboro, Tennessee, USA
Search for more papers by this authorDaniel R. Neuville
CNRS-Géomatériaux, Institut de Physique du Globe de Paris, Sorbonne Paris Cité, 1 rue Jussieu, Paris, France
Search for more papers by this authorJohn S. McCloy
School of Mechanical and Materials Engineering and Materials Science and Engineering Program, Washington State University, Pullman, Washington, USA
Search for more papers by this authorCorresponding Author
Ashutosh Goel
Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854 USA
Correspondence
Ashutosh Goel, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA.
Email: [email protected]
Search for more papers by this authorNikhila Balasubramanya,
Zhenxuan Sun,
Mostafa Ahmadzadeh,
Saeed Kamali,
Daniel R. Neuville,
John S. McCloy,
Ashutosh Goel,
Nikhila Balasubramanya
Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854 USA
Search for more papers by this authorZhenxuan Sun
Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854 USA
Search for more papers by this authorMostafa Ahmadzadeh
School of Mechanical and Materials Engineering and Materials Science and Engineering Program, Washington State University, Pullman, Washington, USA
Search for more papers by this authorSaeed Kamali
Mechanical, Aerospace and Biomedical Engineering Department, University of Tennessee Space Institute, Tullahoma, Tennessee, USA
Department of Physics and Astronomy, Middle Tennessee State University, Murfreesboro, Tennessee, USA
Search for more papers by this authorDaniel R. Neuville
CNRS-Géomatériaux, Institut de Physique du Globe de Paris, Sorbonne Paris Cité, 1 rue Jussieu, Paris, France
Search for more papers by this authorJohn S. McCloy
School of Mechanical and Materials Engineering and Materials Science and Engineering Program, Washington State University, Pullman, Washington, USA
Search for more papers by this authorCorresponding Author
Ashutosh Goel
Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey, 08854 USA
Correspondence
Ashutosh Goel, Rutgers, the State University of New Jersey, Piscataway, NJ 08854, USA.
Email: [email protected]
Search for more papers by this authorAbstract
Spinel crystallization is known to be detrimental to the operation of Joule heated ceramic melters during the vitrification of iron-rich high-level nuclear wastes (HLW) into borosilicate glasses. The literature on this subject focuses on tackling the problem by developing empirical constraints to design compositions, which limit the fraction of spinels formed in the melter or by developing empirical models to predict the settling behavior of spinels in the melter as a function of the glass composition. While these empirical models can predict the behavior of most of the compositions, they are not failsafe as there are always some compositions, whose behavior is beyond the predictive ability of these models. This can lead to undesirable situations during the vitrification of the nuclear waste, and therefore an in-depth investigation of the chemo-structural descriptors controlling the crystallization behavior in these glasses is warranted. Accordingly, the present study aims to understand the impact of non-framework cation mixing (i.e., Li+/Na+ and Ca2+/Na+) on the structure (through Raman spectroscopy and Mössbauer spectroscopy) and crystallization behavior (through XRD, SEM-EDS, and vibrating sample magnetometry) of iron-rich model HLW glasses in the system: (mol.%) x MyO–(25−x) Na2O–9.12 B2O3–6.4 Al2O3–51.25 SiO2–7.22 Fe2O3–0.38 MnO–0.08 Cr2O3–0.55NiO (MyO = Li2O or CaO).
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